The invention pertains generally to automated sewing operations and, more particularly, to automated sewing and mattress component product operations.
Mattresses have traditionally been provided with handles on the vertical side panel or xe2x80x9cborderxe2x80x9d material which covers the side of the mattress, between the top and bottom surfaces. Such border handles are most commonly in the form of a rope or elastic cord, with the ends extending through grommets in the border material and knotted or stapled inside the mattress. The assembly of such handles is labor intensive, requiring measurement for grommet placement, operation of a grommet press, and insertion and securement of each end of the handle through the grommet.
More recently, handles made of a strip of fabric have been sewn to the border material. This requires that each end of the handle is secured by a substantial stitch pattern, such as a box with an X stitch pattern inside the box, in order to give the attachment sufficient strength. To sew a multi-dimensional pattern requires that the mattress border, with the handle in place on top of it, be moved in different directions on a platform under the sewing needle. Also, the ends of the handle can be folded under to double the thickness of material and further increase the strength of the handle. This can be done by hand, or by clamping the handle (with the ends folded) against the border and moving the clamped pieces by an automated carriage assembly, by use of an xe2x80x9cX-Yxe2x80x9d sewing machine. For example, the Mitsubishi PLK series sewing machines are equipped with an X-Y translation carriage mechanism, to which a clamping assembly can be attached, as described in U.S. Pat. Nos. 5,520,129 and 5,738,029. The ""029 patent describes certain modifications to the stock Mitsubishi carriage assembly to increase the X-direction range of motion of the entire assembly, to position an opposite end of a mattress handle under the sewing head. This requires a large amount of repeated mechanical motion for high speed continuous production. Also, the ""029 patent requires that each handle be folded and inserted into a clamp by hand, and that the border material be advanced by hand to position it for attachment of the next handle.
Other machines have been developed which automatically fold material prior to placing it in position on another piece of material for sewing. This is common, for example, in the automated attachment of belt loops, such as described in U.S. Pat. Nos. 3,699,907; 4,385,571 and 4,393,800. Although such machines are functional, they do not represent the most efficient and flexible means of mass producing sewn articles, or to produce a specific component in its entirety such as a mattress border.
The present invention overcomes these and other disadvantages of the prior art, by providing an automated machine for producing measured and cut mattress borders with end folded handles attached by sewing. In accordance with one aspect of the invention, there is provided a machine for automatically producing a mattress border with at least one handle sewn to the mattress border material. The machine includes a spool of border material; a border material feed mechanism for feeding border material from the spool of border material; a spool of handle material; a handle material feed mechanism operative to feed and cut handle material from the spool of handle material; a handle cutter for cutting a handle from the handle material; a sewing platform over which the border material passes; a handle folder assembly for folding ends of a handle under prior to placement of a folded handle on the border material at a position where the folded handle is to be sewn to the border material, the handle folder assembly having: a folding plate having first and second ends; a folding blade at each end of the folding plate, each folding blade operative to descend down upon an end of a handle which extends beyond an end of the folding plate, and further operative to move underneath an end of the folding plate to fold the end of the handle under the folding plate; a clamp fork positioned over each end of the folding blade and operative to be lowered upon a folded end of the handle, and operative to move the handle off of the folding blade and on to the border material; a double frame handle press operative to frame and compress each folded end of the handle material positioned on the border material, and to move each folded end of the handle upon the sewing platform and under a sewing needle in a sewing pattern which attaches the folded ends of the handle to the border material.
In accordance with another aspect of the invention, there is provided a machine for automatically sewing ends of a fabric handle to a mattress border, the machine having: a supply of border material; a supply of handle material; a handle folding assembly; a double frame handle press; a sewing platform, and a sewing head; drive rollers for drawing border material from the border material supply onto the sewing platform; drive rollers for drawing handle material from the handle material supply into the handle folding assembly; a handle material cutter for cutting a length of handle material from the handle material supply; the handle folding assembly having: a folding plate with first and second ends about which ends of a piece of handle material are folded; folding blades which are actuated to descend down upon the ends of the handle material and under the folding blade; folded handle transfer arms which transfer the handle material with the ends folded from the folding blade on to the border material on the sewing platform; and a double frame handle press which compresses down upon the handle on the border material.
And in accordance with still another aspect of the invention, there is provided a material folding device operative to fold a portion of a piece of material under a plate and to transfer material in a folded condition, the device having: a folding plate having a planar surface for supporting at least a portion of material to be folded, and ends beyond which a piece of material may extend; at least one material holding device above the folding plate, the material holding device being controllable to extend downward into contact with a piece of material on the folding plate, and at least one folding blade operative to extend downward past an end of the folding plate and to extend under an end of the folding plate.
And in accordance with another aspect of the invention, there are provided various post-production modules in connection with the machinery of the system, including a folding module which folds a mattress border into a bundle; a closing module which sews together the ends of the border material to form a closed loop border ready for attachment to a mattress; a printing module operative to apply indicia to each border; a wrapping module operative to wrap each completed border in a packaging material for inventory storage or transfer, and a stacking module for presenting completed and packaged borders for subsequent handling. A vent installation module is also described in connection with the machinery of the invention.
Flexible process control of each aspect of the system enables selective end-product variation, such as the number and location of handles attached to the border material, and the number and location of vents installed.
These and other novel aspects of the invention are described with specific reference to the accompanying Figures.